The subject invention pertains to bread spread compositions (e.g. margarines). These compositions consist of an emulsion of an oil or fatty phase and an aqueous phase. The physical characteristics of a finished margarine such as solids content properties, spreadability, and ease of melting in the mouth, are to a large extent determined by the constituents which make up the fatty phase of the emulsion.
Margarine should melt readily in the mouth to avoid a sensation of "waxiness" or "stickiness" and to have a satisfactory flavor. This means there must be almost no fatty material in the solid state at or near body temperatures. On the other hand, at temperatures of use the margarine must be capable of being spread and this requires that some portion of the fatty material be in the solid state at that temperature, but not so much that the margarine is hard and difficult to spread and not so little that the margarine will "slump" or lose its shape.
In addition, it is usually preferred to produce a margarine product that duplicates or approaches the appearance of butter. In general, however, margarines are formulated to have better physical stability at high temperatures than butter and therefore can be stored in both refrigerated or non-refrigerated storage. In specific cases margarines can be produced deliberately different from butter in other characteristics, i.e. margarine can be made spreadable at refrigerated temperature. This is particularly true of the newer type so-called soft margarines which are packaged in tub form.
When some margarines are heated above about 70.degree. F., part of their liquid oil content may start to seep or "oil-off" from the body of the margarine to the lower surfaces. This seepage increases with increase in temperature. If it becomes excessive, liquid oil can leak, soiling the container, In addition to making the package unsightly and oily to the touch, the oil is more susceptible to rancidity because of the greater exposure of the oil to the air. Further, since margarine contains an aqueous phase, bacterial or mold contamination can also occur.
It is generally recognized therefore that margarines must have sufficient heat resistance to resist oil-off under trade conditions.
The conventional way of improving heat resistance of a margarine is to increase the level of higher melting saturated (and trans unsaturated) solid fats in the fatty phase. However, such an increase, though improving the heat resistance of the margarine, results in an increased solids content and hence a significant loss in the eating quality or "melt in the mouth characteristics" of the margarine. It is also recognized that inclusion of saturated fats in the diet is undesirable from a coronary health standpoint. There is, therefore, a need for solid fat-like materials which can control oil seepage in margarines and, at the same time, maintain good eating quality. There is also a need to provide fat-like materials for margarine use which can replace saturated fats.
U.S. Pat. No. 3,600,186, Mattson et al. issued Aug. 17, 1971 discloses solid and liquid fatty acid esters of certain sugars and sugar alcohols which have the physical properties of natural fats and oils but are nondigestible. The reference teaches that these compounds can be used as total or partial substitutes for natural fats in foods, including margarine and dairy products.
European Patent Application 233,856, Bernhardt, published Aug. 26, 1987 discloses compositions comprising sucrose polyesters having specified physical characteristics and triglycerides. Margarine is one of the types of compositions mentioned.